Aviation
emissions reflect the level of overall aviation activity. The growth of
air travel for the past several decades has been very rapid. Demand for
travel services, both passenger travel and freight transportation, is
increasing substantially.

According to the
U.S. Bureau of Transportation Statistics a 21.5 percent increase in
population, 32 percent increase in the labor force, and 90 percent
increase in GDP between 1980 and 2000 have driven this demand.

The chart
shows the growth of aviation and the economy. Demand for air travel
grows as the economy grows and prosperity increases. Over the long term,
we expect that demand for air transportation will continue to grow
rapidly to support our economic productivity, our quality of life, and
our national security.

More and more
the worldwide transportation system is becoming an integrated
transportation network. For most long distance travel, however,
aviationís speed, convenience, and cost overcome consideration of
other travel modes.

It only faces
competition on short trips or when moving low value or high volume
products. Looking to the future, the forecast is for continued
strong growth as shown in the following graph.

This is
consistent with the demand for transportation generally, which is
increasing largely in response to very positive structural changes
in both the domestic and global economies.

As a result, growth of
the aircraft fleet and expansion and further development of existing
airports are expected. This also means that emissions from aviation
activity are expected to grow and concerns about aviation emissions
will also grow.